Raman laser cooling of solids
نویسنده
چکیده
A new approach is proposed for 3-D laser cooling of solids. Stimulated Raman scattering on a narrowband electronic transition is used in conjunction with 1-photon optical pumping on a broadband transition to provide a mechanism that cools all the vibrational modes of solids while conserving energy and momentum, photon by photon. The individual steps in the 2-photon Raman process are 4f–5d and 5d–4f transitions which are electric-dipole-allowed (broadband) transitions that form a L-system. By contrast, the 2-photon transition between the 4f states of the rare earth ion is narrowband. By considering examples of Ce3þ ions in Y3Al5O12 and CeF3, elevated transition rates are predicted to offer substantial improvement over anti-Stokes fluorescence cooling when all 1-photon detunings exceed their corresponding Stokes shifts. & 2012 Elsevier B.V. All rights reserved.
منابع مشابه
Solid State Characterization of Sodium Eritadenate
Knowledge of the solid state is of great importance in the development of a new active pharmaceutical ingredient, since the solid form often dictates the properties and performance of the drug. In the present study, solid state characteristics of the sodium salt of the candidate cholesterol reducing compound eritadenine, 2(R), 3(R)-dihydroxy-4-(9-adenyl)-butanoic acid, were investigated. The co...
متن کاملAdvances in Laser Cooling of Solids
We review the progress on laser cooling of solids. Laser cooling of ion-doped solids and semiconductors is based on the anti-Stokes fluorescence, where the emitted photons have a mean energy higher than that of the absorbed photons. The thermodynamic analysis shows that this cooling process does not violate the second law, and that the achieved efficiency is much lower than the theoretical limi...
متن کاملEntropy and efficiency in laser cooling of solids
The thermodynamics of laser cooling of solids is analyzed. Using the general theory of radiation entropy, the important roles of the optical frequency and the photon distribution function in determining the radiation entropy are identified. The usefulness of a narrow-band approximation is established for a wide range of radiant sources. This approximation is then applied to compare the entropie...
متن کاملMaterials for Optical Cryocoolers
Vibration free cooling of detectors to cryogenic temperatures is critical for many terrestrial, airborne, and space based instruments. Cooling of solids by anti Stokes fluorescence is an emerging refrigeration technology that is inherently vibration free and compact, and enables cooling of small loads to cryogenic temperatures. In this Highlight, advances in laser cooling of solids are discusse...
متن کاملLaser Micro-Raman Spectroscopy of CVD Nanocrystalline Diamond Thin Film
Laser micro-Raman spectroscopy is an ideal tool for assessment and characterization of various types of carbon-based materials. Due to its special optical properties (CrN) coated stainless steel substrates. NCD films have been investigated by laser micro-Raman spectroscopy. The fingerprint of diamond based materials is in the spectral region of 1000-1600 cm-1 in the first order of Raman scatter...
متن کامل